A new study suggests dogs use their facial expressions to communicate

It likely won't come as a surprise to many dog owners, but a new study suggests that dogs use facial expressions to communicate with their humans.

The study, published in the journal Scientific Reports, tracked canine-human interactions of 24 family dogs of average training, reports Nicola Davis for the Guardian. The researchers recorded the dogs' facial movements on video in four different instances: Either a human directly faced Fido or turned away, with or without food. Researchers then scrutinized the footage frame by frame to watch how the muscles on the pooches' faces moved in each new situation.

The results suggest that dogs indeed use their faces to attempt communication. The dogs produced more than twice as many identifiable facial expressions when people were looking directly at them than away. And though it may be surprising to those with "food-motivated" pups, it didn't seem to matter whether the food was present during these interactions or not; dogs still used their faces to communicate, reports Alessandra Potenza of The Verge. This suggests that dogs understood when humans are looking at them and change their facial expressions depending on the situation.

One of the most common expressions the dogs used was the heart-wrenching "sad puppy" look, in which the dog makes its eyes appear larger by raising its eyebrows, writes Michael Greshko of National Geographic.

Primates have been the only non-human animals known to use different facial expressions in response to who's looking at them, reports Emma Young of Nature. Just like in people, those expressions are likely intended to communicate a variety of emotions, feelings and reactions. But this latest study suggests that dogs also have quite a range of nonverbal expressions.

"Domestic dogs have a unique history—they have lived alongside humans for 30,000 years and during that time selection pressures seem to have acted on dogs' ability to communicate with us," says Juliane Kaminski, a researcher at University of Portsmouth and lead author of the study, says in a statement.

Human-dog relations have long fascinated scientists. Past studies have shown that locking eyes with Fido forges stronger dogs-human relations.​ Other research suggests that some people may even accurately be able to read dog expressions. Though we are still far from knowing what's going on in those adorably fuzzy noggins, each new canine study is giving clues to their thought process. And perhaps one day, we'll be just able to read their brain waves to find out.